The present invention relates to apparatus for cutting one or more layers of insulation or other materials surrounding a wire or cable and selectively stripping such insulation off the wire. More specifically, the invention relates to insulation cutting and stripping apparatus of the rotary blade type which is digitally programmed and controlled.
The prior art includes various forms of rotary blade wire insulation cutters and strippers, including that of U.S. Pat. No. 4,745,828, and other patents discussed therein, wherein the conductor is inserted linearly against a stop and gripped between a pair of movable jaws. A pair of cutting blades mounted at one end of respective pivot arms are moved away from and toward one another by advancing and retracting a cone between the ends of the arms opposite the blades. The stop which is contacted by the end of the wire to be stripped is on the opposite side of the blades from the gripping jaws, whereby the blades must be open (apart) as the wire is inserted and the respective positions of the stop and the blades must be precisely controlled. One of the objects of the present invention is to provide a rotary blade wire insulation cutter and stripper wherein the blades are closed (i.e., their cutting edges are together) as the wire is inserted, and the blades themselves provide the stop for wire insertion.
The pivot arms and the cone by which they are pivotally moved are mounted upon a carriage and are jointly movable in a direction along the wire axis by a preselected distance to establish the desired length from the end of the wire to the cut. The cone is then moved linearly as the assembly is rotated, causing the arms to pivot and the blades to move towards one another to establish the desired depth of the cut. In the prior art apparatus, such movements are monitored by potentiometers, and controlled by the resulting analog signal. Another object of the present invention is to provide entirely digital means for controlling movement of the elements to establish both the length and the depth of cuts made by the blades.
The jaws which grip the wire as it is cut are moved in an accurate path toward and away from the wire in the prior art apparatus, which may result in inaccurate centering as wires of differing diameters are gripped by the jaws. Furthermore, the jaws provide the sole means of support for the wire. Additional objects of the present invention are to provide automated wire cutting and stripping apparatus with improved wire gripping, centering and support means.
In a more general sense, the object of the invention is to provide novel and improved, fully automated cutting and stripping apparatus for wire coverings which is compact, durable, efficient, versatile and highly accurate.
Other objects will in part be obvious and will in part appear hereinafter.